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111.
进行受精液中添加不同浓度的β-ME、BSA和咖啡因对猪卵母细胞体外受精及其早期发育的影响试验。结果表明,在受精液中添加β-ME(2、10、50μmol/L)对猪卵母细胞体外受精后的早期发育无显著促进作用,当添加浓度过高(250μmol/L)时对早期胚胎发育反而不利;在受精液中添加咖啡因(1、2、4mmol/L)对猪卵母细胞体外受精后的早期发育无显著的促进作用;在受精液中添加BSA(0.1%、0.2%、0.4%、0.8%)对猪卵母细胞体外受精后的早期发育有一定的促进作用,并以添加0.4%BSA的效果最好。  相似文献   
112.
 【目的】研究探讨卵丘细胞的完整性在支持和促进猪卵母细胞成熟过程中发挥的重要作用以及卵丘与卵母细胞互作的分子机理。【方法】对具有完整致密卵丘细胞包裹的和无卵丘细胞包裹的猪卵母细胞进行了体外成熟培养试验,应用mRNA差异显示(DDRT-PCR)和半定量反转录PCR技术(RT-PCR),对这2类猪卵母细胞中mRNA的差异表达进行研究,得到了14条差异表达条带,经过回收、克隆、测序后,再运用半定量(RT-PCR)进行检测。【结果】体外培养的裸卵细胞的各项成熟指标均低于卵丘-卵母细胞复合体。3个基因(PELP1,Myo5b and CAST)和一条新EST序列在有卵丘和无卵丘的猪卵母细胞中表现出差异表达。分离得到的差异表达基因在雌激素受体调节、细胞膜间的信息传导和细胞器物质运输等过程中发挥重要的作用。【结论】这些差异基因可能参与了卵丘细胞与卵母细胞间的相互作用,对卵母细胞的成熟具有重要作用。  相似文献   
113.
二甲基亚砜(DMSO)、丙二醇(PROH)、乙二醇(EG)和甘油(GL)4种冷冻保护剂程序化冷冻牛GV期卵母细胞的结果表明,EG和PROH的保护效果比GL和DMSO好。4种不同冷冻方法冷冻保存牛GV期卵母细胞,比较解冻后卵母细胞的体外成熟率、受精后卵裂率。结果表明,在程序化冷冻法与细管玻璃化法(Straw)之间的差异不显著(P>0.05),在开放式拉管法(OPS)与毛细玻管法(GMP)之间的差异不显著(P>0.05);但OPS和GMP与程序化冷冻法和Straw之间的差异极显著(P<0.01)。玻璃化冷冻效果优于程序化冷冻。说明GMP和OPS玻璃化冷冻优于Straw玻璃化冷冻。说明可以采用GMP方法冷冻保存牛GV期卵母细胞。  相似文献   
114.
试验旨在探究玻璃化冷冻对驴卵母细胞发育的影响,寻求驴卵母细胞冷冻的最佳条件。通过对不同发育时期的驴卵母细胞进行玻璃化冷冻,冷冻复苏后分别进行成熟培养和孤雌激活,并对GV期未冷冻组(对照组)、GV期冷冻组、IVM-M Ⅱ冷冻组卵母细胞微丝和线粒体超微结构进行免疫荧光标记,统计冷冻复苏后卵母细胞形态正常率、成熟率、孤雌激活卵裂率、超微结构正常率。结果表明,GV期冷冻组卵母细胞的形态正常率与GV期未冷冻组(对照组)间无显著差异(P>0.05),成熟率和卵裂率均显著低于对照组(P<0.05);IVM-M Ⅱ冷冻组的卵裂率显著低于对照组(P<0.05),且卵裂后细胞发育受到阻滞。冷冻组微丝在皮质区分布明显减少的卵母细胞数目增多,冷冻组卵母细胞的线粒体数量明显低于对照组,由此可以说明冷冻对卵母细胞超微结构有损伤,从而导致复苏后成熟率下降,影响卵母细胞的受精和体外发育,且GV期冷冻组较IVM-M Ⅱ冷冻组在微丝与线粒体结构上有较小损伤,发育状态较好。  相似文献   
115.
Oxidative stress inevitably occurs during oocyte maturation in vitro. α-lipoic acid (α-LA) has a strong antioxidant capacity, but the effect of α-LA on parthenogenetic activation of oocytes was rarely reported. This study aims to investigate the effect of supplementing α-LA to in vitro maturation medium on the subsequent developmental ability of goat parthenogenetic embryos during oocytes maturation. In the study, the goat cumulus-oocyte complex was divided into the experimental (with 25 μmol/L α-LA) and the control (without α-LA) groups. Oxidase expression was measured using RT-qPCR. After 18–22 hr of maturation, the oocytes were then parthenogenetic activated. The total antioxidant capacity of embryos was measured after 0, 24, 48, 72 and 96 hr of culture. Rates of oocyte maturation and the rates of development for parthenogenetic embryos in the α-LA group were significantly improved by 7.88% (p < .05) and 5.41% (p < .05) compared with those in the control group, respectively. After 24 hr, the difference in total antioxidant capacity was extremely significant in both groups. An evident decrease in the control group and a minor decrease in the α-LA group were observed (p < .01). The ratio of inner cell mass cells to the total cell number of blastocysts in the α-LA group increased compared with that in the control group (p < .05) on day 8. α-LA significantly promoted the expression of SOD and GPX4 of parthenogenetic blastocysts and maturated oocytes. α-LA (25 μmol/L) improved the maturation rate and the developmental competence of the parthenogenetic activation of oocytes, which might be mediated by maintaining the total antioxidant ability of oocytes during the culture period.  相似文献   
116.
脉冲次数和卵龄对小鼠卵母细胞电活化效果的影响   总被引:2,自引:0,他引:2  
以一定电场条件、不同次数的电脉冲刺激注射HCG后不同时间(15、17、19、21和25h)小鼠卵母细胞,研究了不同电场条件下脉冲次数和卵龄对卵母细胞活化效果的影响。  相似文献   
117.
Roles of trifluoperazine and verapamil in the oocyte maturation and cumulus expansion of bovine cumulus-oocyte complexesRoles...  相似文献   
118.
培养液体积对牛卵泡卵母细胞IVM效果的影响   总被引:2,自引:0,他引:2  
研究了不同的培养液体积 ( 10 0 μl、40 0 μl、2ml)对牛卵泡卵母细胞的体外成熟及随后的发育能力的影响。结果表明 ,采用四孔培养板用 40 0 μl培养液 (上覆灭菌矿物油 )培养卵母细胞 ,其体外成熟率及发育率与微滴 ( 10 0 μl)培养的相应指标无显著差异 (P >0 0 5 ) ,但二者均显著优于 2ml体积的培养体系  相似文献   
119.
The aim of this study was to investigate the ovarian follicular development, developmental competence of oocytes, and plasma anti‐Müllerian hormone (AMH) levels of Japanese wild boar crossbred (wild hybrid) gilts, whose litter size is inferior to that of European breeds. Ovary and plasma samples were collected from two different breeds of gilts (wild hybrid and Large White breeds). The ovaries from the wild hybrid gilts had a lower average numbers of secondary follicles and vesicular follicles in ovarian cross‐sections and of good quality oocytes collected from ovarian follicles as compared with those from Large White gilts (< 0.05). The development rate to the blastocyst stage of good quality oocytes after in vitro maturation, fertilization and culture was also lower (< 0.05) in wild hybrid gilts than in Large White gilts. Plasma AMH levels with >0.16 ng/ml were detected in 8.3% of the examined wild hybrid gilts and 33% of the Large White gilts. These results indicate that the low reproductive performance of wild hybrid breed may result in part from low numbers of vesicular follicles and good quality oocytes, and low developmental competence of oocytes. Moreover, plasma AMH levels may support low number of vesicular follicles in ovaries of wild hybrid gilts.  相似文献   
120.
Ovarian xenografting makes it possible to obtain oocytes with fertilization ability from immature pigs of Western breeds. In this study, we applied these methods to the Meishan, an indigenous Chinese pig breed, and investigated the developmental competence of oocytes grown in their neonatal tissue after grafting into nude mice. First, mice harboring neonatal ovarian tissue were infused with follicle stimulating hormone (FSH) (62.5 U/ml) for 13 days starting at 10, 30, and 60 days after vaginal opening (D10‐, D30‐, and D60‐FSH groups, respectively). Development of antral follicles and their oocytes was most enhanced in the D60‐FSH group. For the next step, we examined the in vitro maturation ability of the oocytes recovered from host mice after infusion with FSH at a dose of 62.5 U/ml or 125 U/ml (FSH‐62.5 or ‐125 group) for 13 days starting at 60 days after vaginal opening. Many more oocytes with maturation ability were obtained from the FSH‐125 group. The FSH‐125 mature oocytes were fertilized in vitro, as shown by formation of male and female pronuclei, but did not reach the blastocyst stage. These results indicate that Meishan neonatal ovaries are able to produce oocytes with fertilization ability after being grafted into nude mice.  相似文献   
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